Comparative study between cardioprotective effects of intermittent antegrade blood cardioplegia with terminal warm blood reperfusion ( hot-shot ) versus intermittent antegrade blood cardioplegia in pediatric cardiac surgery

Background: Terminal warm blood cardioplegia (hot-shot), has been shown to enhance myocardial protection in adult cardiac surgery. The aim of current study is to evaluate terminal warm cardioplegic blood reperfusion compared to conventional reperfusion to determine whether it has a beneficial cardioprotective effect during pediatric cardiac surgery. Methods: This prospective study was carried out in Ain Shams University Hospital on sixty children scheduled for pediatric cardiac surgery. Patients were randomly allocated into 2 equal groups: Control group (C): 30 patients received intermittent antegrade cold blood cardioplegia. Hot-shot group (HS): 30 patients received intermittent antegrade cold blood cardioplegia with terminal warm blood reperfusion just before declamping. We traced and compared the effect of warm cardioplegic blood reperfusion versus conventional reperfusion on clinical outcome parameters, myocardial oxygen and lactate extraction ratio after declamping and serum level of cardiac troponin I. Results: This study demonstrated higher percentage of spontaneous defibrillation into sinus rhythm in hot-shot group when compared to control group (76.7% versus 33.3% respectively), lower level of inotropic support required for weaning from CBP in hot-shot group when compared to control group (4.4±5.5 versus 10.5±6.5 respectively), lower level of inotropic support required in the ICU in hot-shot group when compared to control group ( 75.4±61.2 versus 122.5±103.2 respectively), less duration of inotropic support required in the ICU in hot-shot group when compared to control group (9.5±7.2 hours versus 14.9±11.8 hours respectively), Myocardial lactate extraction ratio was significantly elevated at all studied time interval in hot-shot group when compared to control group, lower level of Serum troponin I at 4 hours after declamping in -shot group when compared to control group (13.2±8.0 ng/ml versus 31.3±23.1 ng/ml), lower level of Serum troponin I at 8 hours after declamping in hot-shot group when compared to control group (10.0±5.8ng/ml versus 19.1±11.5ng/ml). Conclusions: This study demonstrated that: intermittent cold blood cardioplegia with terminal warm blood cardioplegia offered favorable effect on the clinical outcome parameters in term of higher percentage of spontaneous defibrillation into sinus rhythm and lower level of inotropic support, in comparison to intermittent cold blood cardioplegia. Moreover, intermittent cold blood cardioplegia with terminal warm blood cardioplegia accelerated recovery of aerobic metabolism and reduced the myocardial damage following ischemia / reperfusion injury.